This invention relates to a cutter for pottery or ceramic tiles as architectural material.
FIG. 6 of the accompanying drawings shows a prior art tile cutter of this type, as also is shown in the Japanese utility model provisional publication S.56-156613. In FIG. 6, the cutter includes a horizontal base plate 1', a linear ridge 14' fixed to it, a pair of guide rails (only one shown) 3' extending above and in parallel with the ridge 14' between end supports 2', a slider 5' slidable on the rails 3', a pivotal block 4B' supported on the slider 5' by a horizontal hinge pin 5a', and a manipulating lever 4A' fixed to the block 4B'. The block 4B' carries a cutter blade 8' and a pair of press plates 9'. A tile 13A' can be cut by depressing the lever 4A' at the left end of tile 13A', pushing the lever 4A' to move the slider 5' until the blade 8' makes a straight cut or scratch in the tile surface and leaves the right end of the tile, and then further depressing the lever 4A' to force the press plates 9' against the tile on both sides of ridge 14', thereby breaking the tile along the cut.
As also shown in FIG. 5, the lever 4A, and block 4B' pivot around the single hinge pin 5a'. Because the length T1 of block 4B' is relatively large, the lever ratio T/T1 and force fl are small (f T = fl T1). Because the angle .gamma. between the block 4B' and tile is large, the value of cos .gamma. is small. Eventually, the vertical pressure p on the tile is small (p = f1 cos .gamma.). Accordingly, it is necessary to apply a fairly large force f on the lever 4 to form a cut and to break a tile.